Improvement in furnace-grates



J. A. ALLEN. Furnace-Grates.

No. 212,531. v Patented Feb. 25,1879;

N. PEI'ERS, PHDTO LIfHOGRAPHER WASHINGTON, D C.

UNITED TATE S -|MPROVEMENT IN FU RNACE-G RATES.

Specification forming part of Letters Patent No. 212,531, dated February25, 1879; application filed August 14, 1878.

To all whom it may concern:

Be it known that I, JAMES A. ALLEN, of South Adams, in the State ofMassachusetts, have invented certain new and useful Improvements inFurnaceGrates; and I do hereby declare the following to be a full andexact description of the same, reference being had to the accompanyingdrawings, forming part of this specification, in which- Figure 1 is atopplan view Fig. 2, alongitudinal sectional view 5 Fig. 3, a transversesectional view, and Fi 4 a perspective view of one of thesupporting-blocks.

Similar letters of reference in the several figures denote the sameparts.

This invention relates to that class of furnace-gratesin which looseindependent gratebars are arranged upon supporting-bars provided withspacing and supporting cross-bars. In some of these structuresheretofore the fingers have been formed in the shape of wide flangesprojecting laterally from a supportingbar toward the walls of thefurnace, and constructing air-tlues at the ends of the grate-bars, whilein others the fingers have been constructed with sharp edges or anglesarranged to bear against the sides of the grate-bars, in order to giveadditional space for the air-currents.

The object of my invention is to improve the construction of thesupporting-bars and fingers, and thereby the construction and op-'eration of the entire grate.

Another object of my invention is to improve the means for supportingthe ends of the tin ger-bars.

To these ends my invention consists, first, in afinger-bar orsupporting-bar provided with a series of fingers projecting verticallyfrom its upper surface, the proximate faces of said fingers being flatand slightly inclined from each other from their lower to their upperends, the outside or lateral faces of each finger inclining toward eachother from their lower to their upper ends.

By this construction the grate-bars are properly spaced and are heldfirmly, while the upward draft of the air and the downward move ment ofthe ashes are practically unobstructed.

By dispensing with the angular bearingsurfaces heretofore employed thesupportingbar fingers are rendered much more durable, because lessliable to be destroyed or injured by the action of the heat. A

By changing the construction of the fingers from that of lateralprojections or flanges to that of the vertical tapering projections hereshown, the necessity of arranging the supportin g-bars at or near thewalls of the furnace is avoided, the fingers are made stronger and areless liable to become warped by the action of the heat, and thesupporting-bars are more easily balanced and held in position.

The second feature of the invention consists in combining, with thesupporting-bars thus constructed and arranged, a series of independentgrate bars, made narrow, but deep, decreasing in thickness from theirupper to their lower edge, and beveled downward and inward at theirends, as will be hereinafter described.

The third feature of my invention consists in the peculiar shape of achair or block adapted to be inserted into the walls of the furnace, forthe purpose of receiving and supporting the ends of the finger-barsabove referred to.

In the drawings, A A represent the side walls, and B B the ends, of thefurnace. Into the side walls, at the proper points, are in sertedmetallic castings 0, each consisting of a fiat plate or shank, 0, havinga vertical block or plate, 0 joined to its end, said vertical blockhaving two lateral lugs or projections, 0 0 between which its surfacemay be flush with the surface of the plate or shank c.

The shank or plate cis inserted horizontally into the side walls of thefurnace, leaving the block 0 projecting from the wall, whereby the spacebetween the two lugs 0 forms a socket to receive and hold the ends ofthe supporting-bars of the furnace.

The supporting-bars D D, two or more in number, span the furnace fromwall to wall at the proper distances from the ends 13 B. Each bar D isprovided with a set or series of vertical fingers, d (I. These fingersare arranged with narrow spaces between them, which spaces diminishslightly from the top to the bottom of the fingers.

The fingers, at their lower ends, are of substantially the same width asthe supportingbars, but taper upward till their width is re-' ducedabout one-half, and terminate in rounded upper ends. This constructionof fingers gives a firm support to the grate-bars E, which fit somewhatloosely between them, so as to provide for possible expansion. It also,without obstructing the free movement of the ashes and of theair-currents, provides a considerable surface for the support of thegrate-bars, and thereby prevents the heat from rapidly disintegratingand destroying said surface, and renders the whole structure much moredurable.

The form of the fingers is such, it will be observed, as to give themthe greatest possible strength in every direction laterally, and at thesame time to bring the grate-bars close together, thus enabling thenarrow-edged bars of the simple form and construction which I will nowdescribe to be profitably employed.

These bars E, as shown in Fig. 3, are made with a width at their uppersurface equal to about double the width at their lower edge, theirvertical thickness being from four to six times the thickness of theirupper edge. They are also beveled off at their ends from their upperedges downward and inward to their lower edges. They may be, ifpreferred, provided with lugs e e, projecting laterally from their sidesor downward from. their lower edges, so as to engage with one of thesupporting-bars or its fingers, and thereby hold the grate-bars in theirproper relative position during their alternate expansion andcontraction. Thus constructed, the grate-bars are dropped into placebetween the fingers, and when in place they present a smooth flatgrate-surface,-with narrow and sharply-defined air-spaces between them,which air-spaces widen from top to bottom, to give good clearance forthe ashes and free passage for the air-currents, and with a freeclearance and air-space around the ends of the grate-bars, as well asalong their sides. The grate-bars may be separately removed andreplaced.

Having thus described my invention, I claim as new- 1. In combinationwith a furnace-grate, the supporting-blocks 0, having the fiathorizontal shank-plate c, the projecting terminal block 0, and thelateral lugs 0 all arranged and adapted as and for the purposedescribed.

2. The supporting-bars D, adapted to span the furnace from side to side,and provided with vertical fingers (I, having fiat proximate faces andtapering or inclined sides, constructed aud arranged substantially asdescribed.

3. The combination of the supporting-bars, having the"ertically-arranged and fiat-sided fingers herein shown, with the narrowdeep wedge-shaped grate-bars E, provided with a bevel or clearance bothalong their sides and at their ends, constructed and arrangedsubstantially as described.

JAMES A. ALLEN.

Witnesses:

H. H. WELLINGTON, A. H. ORANDELL.

